Simplify Cloud SQL backup enablement logic

modules/cloudsql-instance/main.tf

@@ -20,13 +20,6 @@ locals {
   is_postgres  = can(regex("^POSTGRES", var.database_version))
   has_replicas = length(var.replicas) > 0
   is_regional  = var.availability_type == "REGIONAL" ? true : false
-  # enable backup if the user asks for it or if the user is deploying
-  # MySQL in HA configuration (regional or with specified replicas)
-  enable_backup = (
-    var.backup_configuration.enabled ||
-    (local.is_mysql && local.has_replicas) ||
-    (local.is_mysql && local.is_regional)
-  )
   users = {
     for k, v in coalesce(var.users, {}) : k =>
     local.is_mysql
@@ -109,7 +102,7 @@ resource "google_sql_database_instance" "primary" {
     }
 
     dynamic "backup_configuration" {
-      for_each = local.enable_backup ? { 1 = 1 } : {}
+      for_each = var.backup_configuration.enabled ? { 1 = 1 } : {}
       content {
         enabled = true
         // enable binary log if the user asks for it or we have replicas (default in regional),